接口超导体具有间隙行为,就像一个高温超导体
C Richter1, H Boschker, W Dietsche
11] Max Planck Institute for Solid State Research, 70569 Stuttgart, Germany [2] Experimental Physics VI, Center for Electronic Correlations and Magnetism, Augsburg University, 86135 Augsburg, Germany.
Nature
|October 8, 2013
概括
研究二维 (2D) 超导体揭示了它们的电子光谱密度如何随着载体耗尽而变化. 随着载体耗尽,超导能差距会增加,反映了高温超导体中的伪差距行为.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 量子力学就是量子力学.
背景情况:
- 了解二维 (2D) 电子系统中的超导性对于高过渡温度氧化铜超导体和未来基于接口的超导体至关重要.
- 在这些系统中运载体耗尽期间,基本超导参数的行为,如状态的光谱密度,仍然不太了解.
研究的目的:
- 实验性地研究2D超导体中状态电子光谱密度的变化,作为载体密度的函数.
- 为了澄清2D电子系统中电荷载体耗尽时超导参数是如何演变的.
主要方法:
- 利用带有平面连接的道光谱测量状态的电子光谱密度.
- 使用导电LaAlO3-SrTiO3接口作为可调节的2D超导体,由电门场控制.
主要成果:
- 在状态密度中观察到大约40微电子伏特的能量差距,与巴丁-库珀-施里弗超导差距函数一致.
- 超导差距被发现随着充电载体耗尽而增加,无论是在低剂量或过度剂量区域.
- 这种行为与临界温度对载体密度的圆顶形依赖形成鲜明对比.
结论:
- 随着载体枯竭的超导间隙的观察到的增加类似于高过渡温度氧化铜超导体中的伪间隙行为.
- 这些发现表明,从超导间隙平稳过渡到类似伪间隙的行为可能是二维超导的一般特征.
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